Friday, August 16, 2013

Bumble Bees and Odor Pollution

Bumble bee and lawnmower

This morning they were mowing the lawn in my condominium. Wanting to leave the nerve racking noise behind, I headed for my favorite wildflower garden at Pennypack Ecological Restoration Trust. Instead of escaping the roar, I was treated to another dose of lawn mowing there. The weather was perfect for observing pollinators, so I stayed despite my discomfort.

Bumble bees were going about their business, gathering supplies for their brood, apparently unconcerned by the cacophony. I would like to think that they are equally immune to the fumes of gasoline, but suspect that it isn't so. When the noise stopped, I wondered: how long do the fumes remain? How far do they reach? How do they affect pollinators?

Pollinators need odor cues to find their food. Flowers emit scents to entice their favorite pollinators. These aromas are carried by the breeze, creating trails that bumble bees pick up in their wanderings. Studies show that it takes them longer to find these trails when gasoline fumes are present. It may not be apparent to observers, but lawn mowing impairs the productivity of bumble bees and other pollen seekers. Needless to say, car traffic has the same effect.
Now, you can hear the sounds of nature


Tuesday, August 13, 2013

Monarch Butterfly, a Case of Mistaken Identity

Male monarch butterfly
© Beatriz Moisset

 A few days ago, I arrived at my favorite native flower garden at Churchville Nature Center with my camera, looking for pollinators as usual. A mother, also with a camera hanging from her neck, was visiting the garden with two children.

Black swallowtail caterpillar on fennel
© Beatriz Moisset

Milkweed tussock moth caterpillar
on common milkweed
© Beatriz Moisset

She pointed at a fuzzy, hairy, colorful caterpillar eating milkweed leaves. "Look at the monarch butterfly caterpillar," she said to the kids.

I couldn't stay quiet, "It is a tussock moth caterpillar," I explained.

"Oh, yes," she saved face by adding, "it will turn into a large moth, the tussock moth."

Later, she moved to a fennel plant and announced: "this is the plant that monarch caterpillars need for food."

The real thing, monarch caterpillar on common milkweed
© Beatriz Moisset
Should I have corrected her again? I would have to explain that monarchs feed only on milkweeds. Black swallowtails are the ones that need fennel. I simply walked away shaking my head.

Monarchs, monarchs, monarchs! I thought. How often people mistake anything else for monarchs?

Tiger swallowtail
© Beatriz Moisset

Just a few days earlier, a gentleman photographer at Pennypack Nature Center was busy snapping shots of something I couldn't see at the time. "There is a monarch right there." He pointed at a gorgeous large black-and-yellow striped butterfly with trailing tails on its wings, nothing like the orange and black monarch.

"It is a tiger swallowtail," I told him.

Fritillary butterfly on butterfly weed
© Beatriz Moisset
Then, I remembered all the times when people look at my framed photo of a fritillary butterfly and ask me if, or even tell me that, it is a monarch. All this sounds like Elvis Presley's sightings.

From pandas to dolphins to monarch butterflies: some animals become iconic. The monarch butterfly is, perhaps, the most iconic of all insects. Entomologist Marlin Rice (Iowa State University) referred to the monarch as the "Bambi of the insect world." This spectacular butterfly acquired its fame, in part due to a movement devoted to preserve the monarch and its remarkable migration. The movement is sponsored by websites such as Monarch Watch, the Monarch MonitoringProject, and a few others listed in the Walter H. Sakai's website. They are all worthy causes that engage the public; these projects can use the income generated by all the publicity.

I applaud the efforts of these organizations. At the same time, I wonder: A poster child is valuable if it raises awareness of a broader issue. The ecological importance of the monarch butterfly is that it is one of many species at risk because of human-caused habitat degradation. Other species may not be as appealing as the poster child, but they deserve our attention, too.

Red admiral, sometimes mistaken for a monarch
© Beatriz Moisset

The real thing, monarch butterfly on common milkweed
© Beatriz Moisset
Milkweeds, Monarchs and More: The Milkweed Community 
List of articles
Beginners Guide to Pollinators and Other Flower Visitor

© Beatriz Moisset. 2013